The present invention is directed to locksmith tools, and more particularly, to a picking tool for tubular locks of the type wherein the front end portion of a cylinder is rotatable within a casing and cooperates with the casing to define an annular keyway in which a tubular key is receivable, the key having a series of recesses on its front end that cooperates with spring biased tumblers in the lock which move parallel to the lock axis.
Tubular key locks are frequently used to gain access to coin boxes of vending machines, on switches that control electrical circuits of automobile burglar alarms systems, on coin boxes of gambling instruments, plus numerous other types of equipment. The tubular key that is accepted by the lock of this type is not as readily duplicated as a more conventional flat key intended for a cylinder lock having a slot-like key receiving aperture. Tubular key locks also have the further advantage that they cannot readily be picked by means of conventional picking tools.
Upon occasion, however, there are legitimate reasons for having a tubular key type of lock picked by a locksmith. Traditional picking devices for the tubular type of lock are not efficient, and generally, even the most skilled locksmith will take a substantial period of time to open a tubular type of lock with such a device.
Previously, such picking devices have been designed to fit only one particular type of lock. In actual practice, there are several different sizes of locks with center pin sequences, offset left and offset right pin sequences. Therefore, the picking tools of the prior art are not adaptable to the nonconventional size of tubular lock, or the offset pin sequences.
Almost all tubular cylinder locks at the present time, include seven (7) in number of tumblers. However, there is currently being manufactured a tubular cylinder lock which includes eight (8), or more tumblers.
Tubular key locks, such as those sold under the trademark "ACE" and "GEM", are frequently used on coin boxes of vending machines and on switches that control the electrical circuits for audible burglar alarm systems.
However, the need still exists for a tool for assisting locksmiths in opening tubular locks. The need also exists for a tool that provides sufficient feedback to an operator to assist in locating the shear points of the tumblers in the lock. A further need exists for a tool that can retain a tumbler in a given position, wherein the shear point is located in an opening position of the lock.